Two pieces of Sunoco news on Monday (Sept. 10, 2018) make it a little harder for Sunoco to be able to finish building the Dragonpipe (Mariner East 2 pipeline). One is an explosion in western Pennsylvania; the other is the complete failure of a horizontal directional drilling (HDD) effort in Delaware County.
The Beaver County explosion. In the early morning, a natural gas pipeline exploded in Beaver County, north of Pittsburgh. It is a brand new pipeline constructed by Sunoco parent Energy Transfer Partners. It had been in operation for only a week.
Fortunately, no one was killed in the explosion. A nearby house went up in flames, but its occupants were able to escape safely. Rain in the area prevented a far worse outcome. Six high-tension power-line towers were also knocked over, cutting power to many in the area.
In a statement, ETP claimed its monitoring system caught the leak, but it still took about an hour for ETP to close the pipeline valves, cutting off the flow of natural gas. After that, the fire was left to burn itself out.
According to an article in the Natural Gas Intelligence blog, the pipeline involved is probably part of ETP’s “gathering system” that delivers raw gas from area wells to the Revolution processing plant in Washington County. That recently-completed plant is designed to remove and separate the highly-volatile “natural gas liquids” from the raw gas and send the purified products through the Dragonpipe to Marcus Hook, on the Delaware River.
The failure of a brand-new pipeline suggests poor-quality construction, something we have seen plenty of signs of here in Delaware and Chester County. Sunoco has been digging up and repairing the coating on sections of pipeline it had buried only a few weeks earlier. There has not been any public disclosure about why this is being done or whether sections of pipeline placed by horizontal directional drilling (which can’t be dug up) may also have coating problems. If the problems are serious and do involve HDD pipe, that’s a major problem for Sunoco.
Sunoco and ETP are gaining a reputation for hasty construction, poor quality control, and dangerous pipelines. This is just the most recent addition to a long list of pipeline problems that make ETP by far the most leak-prone operator in the pipeline business, according to federal statistics.
HDD abandoned at Tunbridge. According to statements by township officials at a public Middletown Township meeting Monday evening, Sunoco has decided to abandon its HDD effort near the Tunbridge Apartments in central Delaware County. This HDD site has had multiple frac-outs and flow-back from aquifers over a period of many months of drilling. The company is now abondoning the partly-completed borehole and filling it with grout. It will be exploring other options.
So what happens next at that site? Sunoco now has only three options that I can think of:
- start a new HDD, with a different depth profile,
- use open trenching instead of HDD, or
- use the “temporary” 12-inch bypass pipeline permanently.
The first option is risky because Sunoco might run into the same problems it has already encountered. There is no word on exactly what those problems are, but I imagine it might be that the drill encountered underground “voids”— air- or water-filled empty spaces. If there were voids leading to the surface, that would explain the multiple frac-outs. Voids are a problem for HDD for two reasons: the drill can’t be steered in a void, and the drilling-mud pressure required to turn the drill bit is reduced when the mud escapes into the void, so drilling is slowed or stopped altogether. There’s a good chance that those problems would be repeated if HDD is tried again.
[Update: I am told that in fact the reason for abandonment was a section of really tough rock up the hill from Tunbridge, and that three drill bits broke in attempting to get through, including one that became stuck there for some time. So voids were not the problem–or at least, not the main problem. That patch of tough rock would presumably be a problem again if a new HDD bore was attempted nearby.]
The second option, trenching, may not be practical in this steep, built-up area. But even if it is, there is a long regulatory process required to obtain permits from the DEP. That’s not going to be attractive to Sunoco.
That leaves the third option: the 12-inch line. From Sunoco’s point of view, that would at least allow them to show something for their efforts. It would allow them to roughly triple the volume of NGLs they can currently ship through ME1. Building the Dragonpipe has become a painful process for them, and—even ignoring the troubles at the Tunbridge stretch—it is far from finished. There are a handful of other sites across the state where Sunoco is having HDD trouble, and some where HDD work hasn’t even started.
What Monday’s events mean for Sunoco. The explosion in Beaver County should bring increased scrutiny of Sunoco’s practices, and reduced public support for their projects. Other, more responsible pipeline operators will probably lose patience and be more supportive of restrictions on Sunoco’s activities, which are spoiling the business for all of them. Politicians and regulators will have a better excuse to slow projects down and force better practices.
The HDD abandonment at Tunbridge will cast a shadow over the whole Dragonpipe effort. Investors will wonder whether the investment is a good one, given yet another set of missed completion deadlines, and given that there are a variety of other NGL delivery options. With Dragonpipe construction delayed for an unpredictable period in Delaware County, Sunoco will be desperate to put the 12-inch bypass pipeline into production. That risky, last-ditch plan needs to be stopped before it gets started.
With these and other recent setbacks, the Dragonpipe is beginning to look a little less like the unstoppable juggernaut it seemed to be a year or two ago, and more like a really bad idea whose true nature is finally becoming crystal clear.